package com.sangeng.filter;

import com.alibaba.fastjson.JSON;
import com.sangeng.domain.ResponseResult;
import com.sangeng.domain.entity.LoginUser;
import com.sangeng.enums.AppHttpCodeEnum;
import com.sangeng.utils.JwtUtil;
import com.sangeng.utils.RedisCache;
import com.sangeng.utils.WebUtils;
import io.jsonwebtoken.Claims;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.security.authentication.UsernamePasswordAuthenticationToken;
import org.springframework.security.core.context.SecurityContextHolder;
import org.springframework.stereotype.Component;
import org.springframework.util.StringUtils;
import org.springframework.web.filter.OncePerRequestFilter;

import javax.servlet.FilterChain;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;
import java.util.Objects;

@Component
public class JwtAuthenticationTokenFilter extends OncePerRequestFilter {

        @Autowired
        private RedisCache redisCache;

        @Override
        protected void doFilterInternal(HttpServletRequest request, HttpServletResponse response, FilterChain filterChain) throws ServletException, IOException {
            //获取请求头中的token
            String token = request.getHeader("token");
            if(!StringUtils.hasText(token)){
                //说明该接口不需要登录  直接放行
                filterChain.doFilter(request, response);
                return;
            }
            //解析获取userid
            Claims claims = null;
            try {
                claims = JwtUtil.parseJWT(token);
            } catch (Exception e) {
                e.printStackTrace();
                //token超时  token非法
                //响应告诉前端需要重新登录
                ResponseResult result = ResponseResult.errorResult(AppHttpCodeEnum.NEED_LOGIN);
                WebUtils.renderString(response, JSON.toJSONString(result));
                return;
            }
            String userId = claims.getSubject();
            //从redis中获取用户信息
            LoginUser loginUser = redisCache.getCacheObject("login:" + userId);
            //如果获取不到
            if(Objects.isNull(loginUser)){
                //说明登录过期  提示重新登录
                ResponseResult result = ResponseResult.errorResult(AppHttpCodeEnum.NEED_LOGIN);
                WebUtils.renderString(response, JSON.toJSONString(result));
                return;
            }
            //存入SecurityContextHolder
            UsernamePasswordAuthenticationToken authenticationToken = new UsernamePasswordAuthenticationToken(loginUser,null,null);
            SecurityContextHolder.getContext().setAuthentication(authenticationToken);

            filterChain.doFilter(request, response);
        }

}
